physiology of sexual response

4 stages of sexual response (Masters and Johnson)

Excitement → plateau → orgasm → resolution

What’s the shortest stage of the 4 stages of sexual response (Masters and Johnson)

Orgasm stage

2 basic physiological processes that occur during the stages of sexual response (Masters and Johnson)

Vasocongestion (congestion of blood — excitement and plateau) and myotonia (muscle tension — orgasm and resolution)

Excitement stage (male sexual response — Masters and Johnson)

Erection, elevated testes, and skin of scrotum tenses, thickens and elevates

Erection occurs with non-sexual stimulation as well and sexual stimulation

True

Morning wood (non-sexual stimulation)

Happens during REM; reflexive involuntary movements of body (nocturnal erections)

Puberty (non-sexual stimulation)

Spontaneous erections

Certain meds/drugs, local anesthesia and asphyxiation (no oxygen) can cause…

Non-sexual stimulated erections

Arteries and veins in the non erect state

Open

Smooth muscles are ___ in non-erect state and ___ in erect state

Contracted ; dilated

What controls the smooth muscles in an erect state

The parasympathetic nervous system (individual must be relaxed)

What does viagara do?

Holds the door open so blood can flow into penis

An erection is a spinal reflex

From sensory input from stimulation of genitals OR conscious perception that goes thru the brain (both = most rigid)

Spinal cord injuries could cause

A lesser erection or painful ejaculation

Plateau stage (male sexual response — Masters and Johnson)

Colour of penile glands deepen w blood flow, Cowper’s gland secretion, testes increase in size and fully elevated to warm/protect sperm, prostate enlarges

Cowper’s gland secretion (plateau stage in male sexual response)

Washes out urinary tract to allow sperm to come thru bc acid in pee kills sperm, internal sphincter closes (pee hole), lubricates glands

Orgasm stage (male sexual response — Masters and Johnson)

Erection /= ejaculation; erection + ejaculation /= orgasm; orgasm /= ejaculation

Pre-mature ejaculation

No erection but u ejaculate — can feel sperm coming out without feeling the good of an orgasm

Just bc you orgasm, does not mean you ejaculate

Synapse in limbic system can be felt without releasing anything, u can have multiple orgasms and only ejaculate during the final one ; orgasm = neurological

2 stages of ejaculation

Emission phase and expulsion phase

Emission phase (first stage of ejaculation)

Close door to urine, fluid from epididymis goes into ejaculatory duct within prostate, seminal vesicles give 60% energy to sperm, prostate secretes 40% of liquid (milky colour), sperm less than 1%, external sphincter (point of no return), involuntary contractions

Expulsion phase (second stage of ejaculation)

Starts once point of no return (external sphincter) has closed

The 2 stages of ejaculation are alkaline

Protects pH

Resolution stage (male sexual response — Masters and Johnson)

Body returns to ungrounded state (15-30 mins (age changes this)), gradual return of pulse rate, blood pressure, breathing rate, refractory period

Refractory period (male resolution stage)

Time during which erection or orgasm are not possible even w stimulation — neurological reset ; females do not have this

Estrogen =

Lubrication

Excitement stage (female sexual response - Masters and Johnson)

Inner labia swells w blood flow, uterus elevates, vaginal lubrication (alkaline and filtered, estrogen dependant)

Plateau stage (female sexual response — Masters and Johnson)

Vagina gets longer and wider (close to cervix especially) so its more hospitable for sperm, entrance of vagina tighter (bc of vasocongestion that swells it), clit retracts under hood (sensitive/painful w direct stimulation), inner labia gets vasocongestion and brightens

Clit has almost double the tactile nerves

True

Orgasm stage (female sexual response — Masters and Johnson)

Never mentioned ejaculation; orgasm produced by stimulation of clit, orgasmic platform (pelvic floor) contracts

Resolution stage (female sexual response — Masters and Johnson)

Goes into non aroused state and blood returns to normal

Grafenberg spot (g-spot)

Spot on anterior wall inside that can produce orgasm ; skene glands (liquid from orgasm) poured into urethra and expulsed (only a tiny bit), larger liquids come from bladder

G-spot does not exist

It is acc the clit stimulated internally thru vagina